Updating a field in structure - One to many mapping - Solidity

Question

I have a structure Student with one to many mapping and pushed values to it.Following is my code:

pragma solidity ^0.4.20;

 struct Student{

  uint id;
  string name;
  uint256 mark;

 }

 mapping(uint => Student[]) StudentDetails;

function addStudent(uint classid,uint id,string name,uint256 mark) public payable{

     StudentDetails[classid].push(Student(id,name,mark));
  }

Now I need to update mark field without updating id and name for each student. How it can be done? Help will be appreciated :)

Answer 1

Refer the following function -

function updateStudent(uint classid,uint studentindex,uint id,uint256 mark) public payable{

     StudentDetails[classid][studentindex].mark = mark;
  }

Hope it helps!